The present invention relates to wrapped bales of the type which, in addition to containing paper pulp, recycled paper or like material also include a casing or wrapper around the bale.
The above wrappers must be secured in some manner. These wrappers have normally been secured in place by means of a number of steel wires wrapped around each individual pulp bale. This method is expensive, and complicates the process of transporting the bales from a pulp mill to a paper mill, for instance. The actual cost of the steel wire also represents a material cost that must be met by the pulp manufacturer. It is also necessary to remove the wrapping wires after the bales have arrived at the paper mill, and prior to the bales being fed into a bale shredder. This requires the provision of separate wire cutting equipment and also requires separate handling of the wire scrap that remains.
Several different methods for resolving this problem have been proposed. For instance, U.S. Pat. No. 3,792,563 proposes a solution in which the wrapper is secured to the pulp bales by means of a dissolvable glue which is applied between the mutually overlapping parts of the wrapper. One drawback with this solution, however, is that the glue constitutes a foreign constituent when entire bales are defibered in the paper mill and thereafter delivered to the paper machines as paper stock. Another drawback is that it takes time for the glue to bind, which can result in an unnecessary bottleneck in the packaging line of the pulp mill. Essentially, the same drawbacks are encountered with the method described in PCT Application No. WO 93/00210, in which dissolvable polyvinyl-alcohol tape is wound around the pulp bales. Swedish Patent No. 503,215 teaches a tool for punching and folding-in flaps of overlapping parts of the wrapping sheets so as to fasten these sheets around the pulp bale. This method requires the use of a complicated device for achieving these effects. The device and method are so complex as to tender their use commercially indefensible.
An object of the present invention is to therefore solve the aforesaid problems, and to enable bale wrappings to be secured in a simple and in an environmentally-adapted manner.
This and other objects have now been realized by the invention of a method of securing a wrapper about a bale intended to be treated comprising inserting at least one fastener pin through the wrapper into the bale, the at least one fastener pin adapted to remain in the bale during the treatment thereof. Preferably, the treatment of the bale comprises dissolving the bale.
In accordance with one embodiment of the method of the present invention, the at least one fastener pin comprises a material adapted to dissolve during the treatment of the bale.
In accordance with another embodiment of the method of the present invention, the at least one fastener pin includes a head for abutment with the outer surface of the wrapper when the at least one pin is inserted through the wrapper, and at least one stem intended to be inserted into the bale.
In accordance with the present invention, these objects have also been realized by the invention of a fastener for securing a wrapper about a bale adapted to be treated comprising a pin including a head for abutment with the outer surface of the wrapper when the pin is inserted into the bale, and at least one stem intended to be inserted into the bale. Preferably, the stem includes removal prevention means for preventing removal of the pin from the bale.
In accordance with one embodiment of the fastener of the present invention, the removal prevention means comprises outwardly facing shoulders. In another embodiment, the removal prevention means comprises outwardly facing hook means.
In accordance with another embodiment of the fastener of the present invention, the pin comprises a material adapted to dissolve during treatment of the bale. Preferably, the material comprises corn starch.